Immunohistochemical Expression of E-Cadherin and ß-Catenin in Oral Squamous Cell Carcinoma.

Background: The E-cadherin/ß-catenin protein complexes are actively involved in the epithelial-to-mesenchymal transition. Alterations in cadherin or catenin expression or function, play important roles in the development of invasive or metastatic phenotypes of cancers. Objectives: The aim of this study was to assess the expression of E-cadherin and ß-catenin in oral squamous cell carcinoma (OSCC) patients and to compare this with their clinico-pathological parameters. Materials and Methods: This was a cross-sectional study to assess the immunohistochemical expression of E-cadherin and ß-catenin in 41 cases of OSCC. Data were analyzed using version 26 of SPSS software. Qualitative data were compared using chi-square statistics. Quantitative data were summarized using mean, standard deviation, and confidence interval and compared using a one-way analysis of variance test. The level of significance was set at P < 0.05. Results: Overall, 95.1% of the cases had positive membrane expression for E-cadherin, while cytoplasmic staining was seen in 90.2% cases. Positive nuclear staining was seen in 46.3% cases. There was a decrease in the percentage of cytoplasmic and nuclear expression of E-cadherin as the OSCC became more poorly differentiated (χ2 = 13.96, P = 0.016). Also, a decrease in the percentage of nuclear expression of ß-catenin in poorly differentiated cases was seen. However, no statistically significant difference was seen in the expression of ß-catenin between the different histologic grades (χ2 = 4.8, P = 0.4). Conclusion: This study shows a reduction in the expression of E-cadherin and ß-catenin as OSCC becomes less differentiated.

A multi-centre evaluation of malignant odontogenic tumours in Nigeria.

INTRODUCTION: odontogenic tumors originate from neoplastic transformation of the remnants of tooth forming apparatus. There are varying degrees of inductive interactions between odontogenic ectomesenchyme and epithelium during odontogenesis, leading to lesions that vary from benign to malignant. Malignant odontogenic tumours (MOTs) are very rare and are classified according to embryonic tissue of origin. Recently, there has been a few changes to the classification of MOTs according to the World Health Organization's (WHO) classification in 2017. This study aims to evaluate and reclassify MOTs, using a multi-centre approach in some major tertiary dental hospitals in Nigeria. METHODS: this study reviewed the clinicopathological data on 63 cases of MOT diagnosed over 25 years in five major tertiary dental hospitals in Nigeria. All MOT cases were reclassified according to the recent revision to the 2017 WHO classification of odontogenic tumours. RESULTS: from a total of 10,446 biopsies of oral and jaw lesions seen at the 5 study centres over the 25-year study period, 2199 (21.05%) cases were found to be odontogenic tumours (OTs), of which 63 were MOT. MOTs constituted 0.60% of the total biopsy cases and 2.86% of OTs. Odontogenic carcinomas presented with a mean age higher than odontogenic sarcomas. According to our 2017 WHO reclassification of MOTs, odontogenic carcinomas, ameloblastic carcinomas and primary intraosseous carcinomas were found to be the top three lesions, respectively. Carcinosarcomas were found to be extremely rare. CONCLUSION: using a multi-centre approach is a robust way to reduce diagnostic challenges associated with rare maxillofacial lesions such as MOTs.

A geographical analysis of ethnic distribution of jaw ameloblastoma in Nigerians.

INTRODUCTION: Ameloblastoma is the most common odontogenic tumour in Nigeria. A definite geographic variation has been observed in the frequency of odontogenic tumors from different parts of the world. However, there is no study on the regional variations in Nigeria. Hence, this study was designed to document the ethnic and geographical distribution of jaw ameloblastoma in Nigeria. METHODS: Archival data on ameloblastoma from 10 health facilities were obtained. Global Moran's I detected geographic clustering in its distribution while Local Getis Ord indicated the location of ameloblastoma clusters. Chi-square tested associations between variables at 0.05 level of significance. RESULTS: A total of 1,246 ameloblastoma cases were recorded in Nigeria. Besides substantial state variations, a South-North gradient was noticed in its distribution. Significant positive spatial autocorrelation was observed in the three major groups while ameloblastoma hotspots were found in the SouthWestern and Northwestern Nigeria. The Igbos had a higher prevalence of ameloblastoma outside their home region than within. CONCLUSION: The study hypothesized that the geographical distribution of ameloblastoma in Nigeria is the result of all or one of the following: the country's tropical climate, migration patterns and health seeking behavior. Hopefully, these claims should lead to further enquiry on the underlying causes.

Descriptive epidemiology of salivary gland neoplasms in Nigeria: An AOPRC multicenter tertiary hospital study.

OBJECTIVES: Accurate diagnosis of salivary gland neoplasms (SGN) in many centers in Africa is limited by poor diagnostic resources and ancillary services. Hence, we have carried out a multicenter epidemiological study to understand the true burden of SGN in Nigeria. METHOD: In this descriptive cross-sectional study, we have deployed resources available to members of the African Oral Pathology Consortium (AOPRC) to examine the burden of salivary gland lesions in Nigeria, using a multicenter approach. Data from seven major tertiary health institutions in northern, western, and southern Nigeria were generated using a standardized data extraction format and analyzed using the Epi-info software (Version 7.0, Atlanta, USA). RESULT: Of the 497 cases examined across the seven centers, we observed that SGN occurred more in females than males. Overall, pleomorphic salivary adenoma (PA) was found to be the most common. PA was found to be the commonest benign SGN while adenocystic carcinoma (ADCC) was the commonest malignant SGN. Regional variations were observed for age group, diagnosis, and gender distribution. Significant statistical differences were found between males and females for malignant SGNs (p-value=0.037). CONCLUSION: We found regional variation in the pattern of distribution of SGN in Nigeria. This is the largest multicenter study of SGN in Nigeria, and our findings are robust and representative of the epidemiology of this neoplasm in Nigeria.

A review of 640 Oral squamous cell carcinoma cases in Nigeria.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is the most prevalent malignant neoplasm in the oral cavity and accounts for 70% to 90% of all oral malignant neoplasms. The aim of this study was to examine the demographic distribution of OSCC in five Tertiary Health centres in Nigeria. MATERIAL AND METHODS: All cases diagnosed as OSCC during the period from 1970 -2014 were retrieved from the records of five teaching hospitals in Nigeria. Hematoxylin and eosin stained histological slides of all cases that had a diagnosis of OSCC were reviewed for confirmation and inclusion. Data from all the centers was collated at the University College Hospital, Ibadan by 2 researchers. The data was entered into and analyzed with the SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). Simple descriptive and comparative analyses were done, with the test of statistical significance set at p ≤ 0.05. RESULTS: A total of 640 cases of OSCC were seen out of 1560 oral malignant neoplasms representing 41% of all the oral malignancies seen. The mean age of occurence of OSCC was 55.5 (±17.0) years and a peak age incidence in the sixth and seventh decades of life. OSCC occurred more in males (60.9%) than females (39.1%) with a male: female ratio of 1.6:1. The well differentiated OSCC with 309 (48.3%) cases, was the most common grade, while the moderately differentiated and poorly differentiated OSCC accounted for 232 (36.2%) and 92 (14.4%) cases respectively. CONCLUSIONS: This study showed that OSCC is more common in males, most commonly seen in the 60-69 age group and the commonest site of occurrence was the mandibular mucosa. The well differentiated OSCC was the most common histology sub-type. Key words:Oral squamous cell carcinoma, tongue, palate, mandible.

A retrospective review of 61 cases of adenomatoid odontogenic tumour seen in five tertiary health facilities in Nigeria.

INTRODUCTION: Adenomatoid odontogenic tumor (AOT) is a benign lesion originating from the dental lamina or its remnants. It is a relatively uncommon neoplasm representing about 3% of all odontogenic tumors. The aim of this study was to examine the clinical and radiological characteristics of AOTs in five major tertiary centres in Nigeria. METHODS: Archival hospital-based data stores of five tertiary health facilities in Nigeria were accessed. Case files and biopsy records were retrieved to obtain relevant information. Data was collected according to a proforma for standardization and entered into and analysed using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). RESULTS: 61 (4.5%) cases of AOT were documented. The age range was 8-46 years with a mean age of 20.4±9.9 years. Male: Female ratio was 1:1.3. The anterior maxilla had 34 (55.8%) cases and the anterior mandible had 20 (32.8%) cases. 40 (65.6%) follicular cases, 20 (32.8%) extra-follicular cases and 1(1.6%) extra-osseous case were found. 31 cases (61.1%) were associated with impacted teeth and the upper canine was involved in 19 (57.6%) cases. CONCLUSION: This study showed AOT to be more common in the maxilla, more in females, most often associated with impacted canines, however, the suggestion of AOT being a "Two third tumour" was not observed in this study.

A retrospective study of 21 cases of malignant odontogenic tumours from two tertiary health centres in Nigeria.

INTRODUCTION: Malignant odontogenic tumours (MOTs) are relatively rare tumours and only few cases have been reported in the sub-Sahara African literature. The aim of this study was to describe the demographic distribution of malignant odontogenic tumours in two tertiary health centres based on the current WHO 2005 classification scheme. METHODS: We reviewed 21 malignant odontogenic tumours out of a total of 374 odontogenic tumours from two Tertiary Health Centres. Information regarding histology, location, patients age and gender for MOTs were analysed using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). RESULTS: Twenty one (5.6%) MOTs out of a total of 374 odontogenic tumours were seen from the two institutions over the study period. The median age for MOTs was 42.0 (± 19.0) years (range = 16-66 years). The male: female ratio was 2.5:1 and 85.7% occurred in the mandible. Ameloblastic carcinoma (AC) with 13 (61.9%) cases was the most common MOT. AC had a mean age of 37.5 (± 11.9) years. AC had a mandible: maxilla ratio of 5.5:1 with majority (84.6%) occurring in the posterior mandible. CONCLUSION: This study showed that MOTs are rare lesions. AC was the most common MOT and majority of MOTs occurred in the posterior mandible of male patients. The study helps to better elucidate the demography of MOTs in sub-Sahara Africans.

Malignant salivary gland tumours of the head and neck region: a single institutions review.

INTRODUCTION: Malignant salivary gland tumours (MSGTs) comprise about 3% of all head and neck cancers; they demonstrate an unpredictable clinical course. The purpose of this study is to review MSGTs seen at a tertiary Health centre, and compare findings with those of previous studies. METHODS: The records of the Department of Oral Pathology and the Department of Pathology, University College Hospital Ibadan were reviewed over a 19 year period and lesions diagnosed as MSGTs according to 2005 WHO histological classification were analysed for age, gender and site using SPSS for Windows (version 20.0; SPSS Inc. Chicago, IL). RESULTS: MSGTs were more common in males (55.2%) than females (44.8%). The mean age of was 47.9 (±17.0) years and peak age was the fifth decade. The parotid gland was the commonest site with 62 (28.1%) cases. The palate was the commonest intraoral site with 61(27.6%). The nose with 19 (8.6%) was the commonest minor extra-oral site. CONCLUSION: The findings were essentially similar to reports from Europe and America. Adenoid Cystic Carcinoma was the most common MSGT in this series. A high proportion of salivary gland tumours in sublingual gland were malignant. The reason(s) for high proportion of MSGTs in sublingual glands requires further investigation.

Immunohistochemical expression of MMP-2 and MMP-8 in oral squamous cell carcinoma.

BACKGROUND: Matrix metalloproteinases (MMPs) are endopeptidases that can degrade extracellular matrix components and affect invasiveness and aggressiveness of oral squamous cell carcinoma (OSCC). The aim of this study was to examine the immunohistochemical expression of MMP-2 and MMP-8 in OSCCs in patients presenting at the Tertiary Health facility in Nigeria. MATERIAL AND METHODS: Formalin-fixed, paraffin-embedded (FFPE) OSCC samples diagnosed between the years 2010 and 2012 were used for his study. The FFPE were processed for MMP-2 and MMP-8 using the specifications of the manufacturer. Two investigators reviewed the slides scoring the pattern and intensity of staining as negative (0), weakly positive (+1), moderately positive (+2) and strongly positive (+3). The data were analysed using version 20 of the SPSS. The level of significance was set at P < 0.05. RESULTS: Twenty-five OSCC consisting of 14 (56%) males and 11 females (44%) were used. The mean age was 54.6 ± 17.9 years. A higher proportion (100%) of poorly differentiated OSCC strongly expressed MMP-2 compared with the well differentiated and moderately differentiated OSSC. There was no significant difference in the expression of MMP-2 amongst the three grades of OSCC (X2 = 2.87; p= 0.17). Only 5 (20%) OSCC cases positively expressed MMP-8. Moderate expression of MMP-8 was only seen in well-differentiated OSCCs. CONCLUSIONS: This study showed that a higher proportion of poorly differentiated OSSC strongly expressed MMP-2. Eighty percent of cases that express MMP-8 were females and moderate expression of MMP-8 was seen only in well differentiated OSCC. Key words:Oral squamous cell carcinoma, MMP-2, MMP-8, immunohistochemistry.

PTCH-1 and MDM2 expression in ameloblastoma from a West African sub-population: implication for chemotherapeutics.

INTRODUCTION: Ameloblastoma is a slow growing, painless odontogenic swelling which can attain sizes that result in severe deformities of the craniofacial complex. It is the most commonly encountered odontogenic tumor in Nigeria. Surgical intervention is currently the method of treatment; however identification of altered molecular pathways may inform chemotherapeutic potential. The Protein Patched homolog 1 (PTCH-1) is overexpressed in ameloblastoma. Also, mutation in the MDM2 gene can reduce the tumor suppressor function of p53 and promote ameloblastoma growth. No study however has characterized the molecular profile of African cases of ameloblastoma with a view to developing chemotherapeutic alternatives. The objective was to characterize the PTCH-1 genetic profile of Ameloblastoma in Nigerian patients as a first step in investigating its potential for chemotherapeutic intervention. METHODS: Twenty-eight FFPE blocks of ameloblastoma cases from Nigerian patients were prepared for antibody processing to PTCH-1 (Polyclonal Anti-PTCH antibody ab39266) and MDM2 (Monoclonal Anti-MDM2 antibody (2A10) ab16895). Cytoplasmic brown staining was considered as positive for PTCH while nuclear staining was positive for MDM2. RESULTS: Moderate and strong expressions for PTCH in ameloblast and stellate reticulum were 78.6% and 60.7% respectively. Only 3 (10.7%) cases expressed MDM2. CONCLUSION: The importance of our study is that it supports, in theory, anti-PTCH/SHH chemotherapeutics for Nigerian ameloblastoma cases and also infers the possible additional use of anti-p53 agents.

Stoichiometric expression of MMP-2/TIMP-2 in benign and malignant tumours of the salivary gland.

The aim of this study was to determine the expression of matrix metalloproteinase 2 (MMP-2) and tissue inhibitors of matrix metalloproteinase 2 (TIMP-2) and the MMP-2/TIMP-2 expression ratio in salivary gland tumours (SGTs). Forty-three FFPE SGTs were prepared for antibody processing to MMP-2 and TIMP-2. Two investigators utilizing Sinicrope's method scored the uptake of immuno-stains. Cytoplasmic staining was considered as positive. Data was analysed using SPSS version 20. The significance level was set at p < 0.05. In benign SGTs, the mean score for MMP-2 was not significantly lower than that of TIMP-2 (p = 0.37). However, the mean scores for MMP-2 stain intensity and proportion were significantly higher in malignant than benign SGTs (p = 0.01 and p = 0.02 respectively). There was no significant difference in the mean MMP-2/TIMP-2 expression ratio of the malignant SGTs according to histological grade and histogenesis (p = 0.4 and p = 0.19 respectively). The MMP-2/TIMP-2 expression ratio has a higher prognostic value than the separate expressions of MMP-2 and TIMP-2.

Clear cell variant of squamous cell carcinoma of skin: A report of a case.

Clear cell squamous cell carcinoma (SCC) is a rare variant of SCC of skin in which ultraviolet radiation has been suggested as possible etiology. This case is that of a 62-year-old male concrete block maker/bricklayer who presented with a 6 months history of a non-healing ulcer on the left side of his face. Histology showed features of malignant epithelial neoplasm composed of islands of large oval to polyhedral malignant squamous cells with eosinophilic to amphophilic cytoplasm and vesicular nuclei and there were areas showing clear cell differentiation and isolated areas of keratin pearl formation. The lesion was also negative for periodic acid schiff, mucicarmine, and alcian blue stains but was strongly positive for AE1/AE3 (immuno-stain). This case showed an aggressive and bizarre clinical presentation but more report of cases are needed to have a better characterization of the clinical presentation and prognosis of this variant of SCC.

Non-doctor consultations and self-medication practices in patients seen at a tertiary dental center in Ibadan.

AIM: The aim of this study was to determine the prevalence of self-medication practices among dental out patients presenting at a tertiary health care center in Ibadan, and to determine factors that are associated with these practices. MATERIALS AND METHODS: All patients presenting over a 4-month period, who consented to participate in the study, had a semi-structured questionnaire, highlighting age, sex, income and educational qualification, history of past practice of self-medication, substances used and reasons for resorting to self-medication administered to them. Data obtained were analyzed with the SPSS 12.0.1 software. Frequency tables were generated and statistical relationship between the variables was analyzed using the Chi-square test. Statistical significance was set at P>0.05. RESULTS: There were 108 (38.03%) males and 176 (61.97%) females. A total of 139 (48.9%) of the respondents claimed that they have been involved in self-medication. 54.7% of the people involved in self-medication were female, while 41.7% were male. There was a statistically significant difference in self-medication between males and females (P=0.001). 71.2% of the respondents had post-secondary education and only 28.8% had secondary education or less. CONCLUSION: Self-medication practices were quite high in this study, and these practices were also prevalent among the educated people. Drug control enforcement needs to be intensified and dental public health education needs to be given greater priority in the overall public health campaigns.